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An Unusual Cause of Chest Pain

Reviewed By Clinical Problems Assembly

Submitted by

Laura J. Hinkle, M.D.

Resident

Department of Medicine

Indiana University School of Medicine

Indianapolis, IN

W. Graham Carlos, M.D.

Fellow

Division of Pulmonary, Critical Care, Allergy, and Occupational Medicine

Indiana University School of Medicine

Indianapolis, IN

Gabriel T. Bosslet. M.D., M.A.

Assistant Professor of Clinical Medicine

Division of Pulmonary, Critical Care, Allergy, and Occupational Medicine

Indiana University School of Medicine

Indianapolis, IN

Submit your comments to the author(s).

History

A 42-year-old African American man presented to the Emergency Department complaining of worsening chest pain and indigestion over one week.  Initial workup included a chest x-ray, which demonstrated an opacity nearly filling the right hemithorax (Figure 1a, 1b).  He was admitted for further evaluation by pulmonary, oncology, and thoracic surgery specialists, determined to be stable, and discharged from the hospital with arrangements made to complete the remainder of his evaluation as an outpatient.  He returned several weeks later with ptosis, dysarthria, dysphagia, and generalized weakness.  A repeat chest radiograph was unchanged.  He was admitted for further diagnosis and treatment.  On the second hospital day he developed acute respiratory failure necessitating transfer to the intensive care unit, intubation, and initiation of mechanical ventilation.

The patient had no significant past medical history and did not take any medications or supplements.  He denied tobacco use, but reported using alcohol and marijuana regularly.  He had not traveled outside of the United States and his family history was negative for malignancies.  A complete review of systems was significant for a 20-pound, unintentional weight loss over the last year and increasing shortness of breath for the past week.

Physical Exam

On presentation to the Emergency Department, his vitals included: temperature of 98.6°F, heart rate of 125 beats per minute, respiratory rate of 18 breaths per minute, blood pressure of 130/78, and pulse oximetry on room air of 92%.   The patient was thin and in no apparent distress.  He appeared to struggle when attempting to swallow water.  Trachea was midline and there was no palpable lymphadenopathy.  There was bilateral ptosis.  Breath sounds were clear on the left and diminished with dullness to percussion on the right.   S1 and S2 heart sounds were normal. The remainder of the exam was unremarkable.

Lab

Initial laboratory workup included a BMP and CBC.  His white blood cell count was 13.9 k/mm3 with 85% neutrophils.  His basic metabolic panel was significant only for a chloride level of 95 mmol/L and a bicarbonate level of 38 mmol/L.  Arterial blood gas obtained on FiO2 of 100% prior to intubation was pH 7.26, PaCO2 of 86 mmHg, and PaO2 of 322 mmHg.

Figures



Figures 1a & 1b: PA and lateral chest x-ray.

Question 1

What is the pathophysiology that best explains this patient’s clinical presentation?

References

  1. Chaudhuri A, Behan PO. Myasthenic crisis. QJM 2009;102:97-107.
  2. Juel VC. Myasthenia gravis: Management of myasthenic crisis and perioperative care. Semin Neurol 2004;24:75-81.
  3. Jani-Acsadi A, Lisak RP. Myasthenic crisis: Guidelines for prevention and treatment. J Neurol Sci 2007;261:127-133.
  4. Lacomis D. Myasthenic crisis. Neurocrit Care 2005;3:189-194.
  5. Duwe BV, Sterman DH, Musani AI. Tumors of the mediastinum. Chest 2005;128:2893-2909.
  6. Maggi L, Andreetta F, Antozzi C, Baggi F, Bernasconi P, Cavalcante P, Cornelio F, Muscolino G, Novellino L, Mantegazza R. Thymoma-associated myasthenia gravis: Outcome, clinical and pathological correlations in 197 patients on a 20-year experience. J Neuroimmunol 2008;201-202:237-244.
  7. Prokakis C, Koletsis E, Apostolakis E, Zolota V, Chroni E, Baltayiannis N, Chatzimichalis A, Dougenis D. Modified maximal thymectomy for thymic epithelial tumors: Predictors of survival and neurological outcome in patients with thymomatous myasthenia gravis. World J Surg 2009;33:1650-1658.
  8. Skeie GO, Romi F. Paraneoplastic myasthenia gravis: Immunological and clinical aspects. Eur J Neurol 2008;15:1029-1033.
  9. Romi F, Gilhus NE, Aarli JA. Myasthenia gravis: Clinical, immunological, and therapeutic advances. Acta Neurol Scand 2005;111:134-141.
  10. De Baets M, Stassen MH. The role of antibodies in myasthenia gravis. J Neurol Sci 2002;202:5-11.
  11. McDaneld LM, Fields JD, Bourdette DN, Bhardwaj A. Immunomodulatory therapies in neurologic critical care. Neurocrit Care 2010;12:132-143.
  12. Lopez-Cano M, Ponseti-Bosch JM, Espin-Basany E, Sanchez-Garcia JL, Armengol-Carrasco M. Clinical and pathologic predictors of outcome in thymoma-associated myasthenia gravis. Ann Thorac Surg 2003;76:1643-1649; discussion 1649.
  13. Raica M, Cimpean AM, Ribatti D. Myasthenia gravis and the thymus gland. A historical review. Clin Exp Med 2008;8:61-64.